The Republican from Florida raised $3 million from April to June, according to a report to be filed with the Federal Election Commission, as the immigration debate was underway in the Senate. It was an increase of more than 30 percent from his fundraising in the first three months of the year.

For his leading role in the immigration debate, Rubio won praise and drew criticism from Republicans. But his latest financial report shows that his base of supporters grew as his profile rose during the heated immigration debate.

Rubio's finance report shows that he has nearly $3 million cash-on-hand in his various political committees, including $980,000 in the Reclaim America PAC and $1.97 million in his Senate re-election committee.

The short-term politics of immigration remain an open question, particularly as the bill draws more criticism by conservatives in the House, but Rubio’s role as a top proponent of the bill seems to have helped his ability to raise money.